Electromechanical starting device for quartz mercury arc lamps



1931: w.--T. ANDERSON, JR, ET AL 1,838,033

ELECTROMEGHQNICAL STARTING DEVICE FOR QUARTZ MERQURY ARC LAMPS FiledJuly 26,. 1930 NVENTOR! m fiwyg ATTORNEY Patented Dec. 22, 1931 UNETEDSTATES PATENT OFFICE 'WILLIAM T. ANDERSON, JR., AND LESTER F. BIRD, OFNEWARK, NEW JERSEY, ASSIGNORS T HANOVIA CHEMICAL AND Is EANUFACTUR-TNGCOMPANY, OF NERVARK, NEW JERSEY, A CORPORATION OF NEW JERSEYELECTROMEGI-IANICAL STARTING DEVICE FOR QUARTZ MERCURY ARC LAMPSApplication filed July as,

This invention refers to starting devices for are lamps containingmercury in a closed envelope, by means of which the mercury is moved tostrike an are between the ends of the arc tube.

There are several methods that have been devised and used for lightingmercury arc lamps. The most common of these is that of hand tipping ortilting the arc tube to strike an arc. Other methods are those ofproducing motion of the mercury by applying heat to portions of the areenvelope, or by pro ducing motion of the envelope by the use of magnetsor solenoids so that motion of the mercury will strike an arc.

By far the larger number of devices are those of the magnet or solenoidtype tilting the envelope to agitate the contained mercury and sostarting an arc.

When the problem of starting an arc is considered in connection withtherapeutic mercury arc lamps in quartz envelopes the lighting problemis much more acute for several reasons. Among the first of these is thecost of the arc tube. It is not desirable to expose a valuable arc lampto sudden motions that may in any way damage the burner.

For this reason the therapeutic lamps of this type have been generallystarted by hand. The burner is ordinarily mounted in a movable supportsuch that the burner is free to move through a vertical arc about apivot near the cathode end of the burner,

- and motion is imparted to the burner by hand through chains or leverarms.

This method of lighting is satisfactory for most purposes, but therehave arisen cases where automatic lighting is more desirable;

j especially when the arc lamp is mounted in a more or less inaccessibleplace. Very often in solarium installations the burner is in such alocation that it is diflic-ult to apply a hand operated device;moreover, it is often desirable that atotally inexperience-d person beable to operate the arc lamp.

Even with hand tilting, care is necessary in order that the burner isnot damaged; and there is too much risk attached to the starting ofthese lamps by inexperienced people.

It is an object of this invention to provide 1930. Serial No. 470,951.

a device which will light a quartz mercury arc lamp safely, quietly,quickly, and without danger to the burner.

This and other advantageous objects are attained by the novelcombination and arrangement of parts hereinafter described andillustrated in the accompanying drawing, which forms a part of thisdisclosure.

The drawing shows diagrammatically the arrangement of the elementsinvolved in the device.

Referring to the drawing, a mercury arc burner 1 is shown in the normalburning and cold position. The burner includes a well 2 of mercuryconnected with the cathode 3, and a well 1- of mercury connected to theanode 5, the electrodes 3 and 5 being connected to a source 6 ofelectrical current.

The burner is supported adjacent the well 2 by an arm 7 pivotallyconnected to a support 8. An arm 9 ad iacent the well 4; is pivotallyconnected to a link 10, the latter being pivoted. to a crank arm 11,fixed to a shaft 12. The arrangement above described enables the anodeend of the burner to be lifted through a vertical are from the normalburner position so that mercury may be caused to flow from the anode endto the cathode end to strike an arc. The normal burner position is suchthat excess mercury will not remain at the cathode end but will flowback to the anode end.

Fixed to the shaft 12 is a cam 13 and a worm wheel 14. the lattermeshing with a worm 15 fixed to the shaft of an electric motor 16. Theworm wheel and worm are for the purpose of speed reduction, andobviously other gear arrangements may be used for such speed reduction.The electric motor is connected. to source 17 of electrical current.

Positioned in the path of cam 18 is a spring member 18 adapted to engagea contact 19 to close a circuit in which is included the elements 20 and21 of a push button switch.

In operation, when the push button is depressed to cause engagement ofthe elements 20 and 21, the circuit is closed through the motor 16, andthe rotation of shaft 12 causes the anode end of the burner to be raisedto strike an arc, and then lowers the anode end to the normal burningposition.

As shaft 12 rotates, spring contact 18 is caused to engage contact 19,which engagement is maintained for a one-half revolution of shaft 12.Since engagement of contacts 18 and 19 will also close the circuitthrough the motor, it will be seen that the push button switch need beonly depressed momentarily.

The cam 13 is positioned so that it will hold the contacts 18 and 19 inengagement all of the time the burner is out of the burning position.

As soon as the burner is back in the burning position the cam 13releases the contacts so that the circuit is broken through the motor. I

When it is desired to continue the tilting of the burner until an arc isstruck, an arm 22 is provided to lock contacts 21 and 21 in engagement.The arm 22 is pivoted at 25 to a suitable support, and normally urgedupwardly into engagement with contact 21 by a spring 23.

Contact 21 is wedge-shaped, and when the push button is depressed, thearm 22 snaps against the flat face of contact 21 and holds the latterinto engagement with contact 20. Now, when the burner is lighted, acircuit is closed through an electromagnet 24, positioned adjacent arm22, and the arm 22 is drawn downwardly to release contact 21 and openthe circuit through the motor.

Obviously, the cam 13 and contacts 18 and 19, will restore the burner tonormal burning position irrespective of the location of burner when anarc is struck and electromagnet 24 is energized, otherwise the motorwould be stopped with the burner out of proper position.

From the above description it will be seen that there has been provideda device for lighting a therapeutic quartz mercury arc lamp with nodanger to the burner, the latter being handled with the gentlestofmotions and being moved to the positions most suitable for speedylighting.

It will also be seen that the device is automatic in its operatiomandcapable of repeating its motions until the burner is lighted.

The foregoing disclosure is to be regarded as: descriptive andillustrative only, and not as restrictive or limitative of theinvention, of which obviously an embodiment may be constructed includingmany modifications without departing from the general scope hereinindicated and denoted in the appended claims.

Having thus described our invention, what We claim as new and desire tosecure by Letters Patent, is:

1. In combination with a mercury vapor are lamp, a device fortilting'the lamp to strike an arc, comprising an electric motor,

a push button switch for momentarily closing an electrical circuitthrough the motor, a normally open switch, means connected to one end ofthe lamp and operated by the motor to tilt the lamp, and cam meansoperawed by the motor to close the normally open switch to maintain thecircuit closed through one-half cycle of the tilting means.

. 2. In combination with a mercury vapor arc lamp, a device'for tiltingthe lamp to strike an arc, comprising an electric motor, a normally openswitch for closing a circuit through the motor, means for locking saidswitch in a closed position, means connected to one end of the lamp andoperated by the motor to tilt the lamp, and an electromagnet forreleasing said locking means when the lamp has been lighted.

3. In combination with a mercury vapor arc lamp, a device for tiltingthe lamp to strike an arc, comprising an electric motor, a normally openswitch. for closing a circuit through the motor, means for locking saidswitch in a closed position, means connected to one end of the lamp andoperated by the motor to tilt the lamp, and means for releasing saidlocking means when the lamp has been lighted.

This specification signed this 21st day of July, 1930.

WILLIAM T. ANDERSON, JR. LESTER F. BIRD.

